1. Field of the Invention
This invention relates generally to input devices, and in particular to reducing friction in input devices.
2. Description of the Related Art
Over the last few decades, the use of computers, and their accompanying input devices (such as mice, trackballs, keyboards, etc.) has become pervasive. The use of several input devices is based upon the movement of the input device itself (e.g., in the case of mice), or upon the movement of some part of the input device (e.g., in the case of trackballs).
Let us consider, in particular, the movement of the part of an input device that controls the movement of a cursor on the screen of an associated display. For example, for a mouse this is the movement of the mouse over a work surface (e.g., a mouse pad, the top of a table, etc.). For a trackball, this would be the movement of the rotating ball relative to its housing. Such movement necessarily involves some friction due to the area of contact between the mouse and the work surface. Such friction increases the effort expended by the user in moving the cursor from one position to another.
Moreover, such friction reduces both the speed of the user's actions as well as the precision of his positioning of the cursor. Further, such friction results may result in more noise when the mouse is moved over the work surface. Reducing friction improve mouse gliding and precision. Further, this helps in reducing/eliminating slip stick—the effect caused by the difference between static and dynamic friction. For these and other reasons, reducing and/or controlling this friction significantly enhance the user experience.
It should be noted, however, that some friction is necessary for some purposes. For instance, a user would not be able to perform the much-used action of double clicking if he were unable to click on the same spot twice (that is, if, due to lack of friction, the mouse moved between the two clicks). Another example is that when the input device is not being used, the input device should not move away from where the user had left it, due to a lack of friction. Thus it is important to control the amount of friction at different times (e.g., depending on the current usage of the mouse).
In conventional devices available today, some steps have been taken to reduce the friction between the mouse and the work surface. Several mice currently on the market use small pieces of low friction materials (such as High Molecular Weight Poly Ethylene (HMWPE), Poly Tetra Fluor Ethylene (PTFE), or Teflon) glued onto the areas of the mouse which come into contact with the work surface (often the “feet” of the mouse on the bottom case). Depending on the material of the work surface and its condition, the friction and the noise between the mouse and the work surface are variable. Further, after some time of use, the feet of a mouse become scratched and friction and noise increase. This is due to the presence of materials like dust, sand, etc. which interfere with the low friction materials used for the feet. Over time, the apparent friction between the work surface and the mouse increases significantly.
None of the conventional devices implement reduction of friction in an effective manner that lasts over time. Further, none of the conventional devices provide the ability to control the friction between the mouse and the work surface at different times and/or under different circumstances.
Thus what is needed is a method and system for effectively reducing the friction between an input device and the work surface. In addition, there is need for a method and system for reducing noise generated by such movement. Further, there is a need for an intelligent management of the reduction of friction, so that lack of friction does not become problematic.